Cutting device



July 29., 1930. E. .1. BATTIE A1,771,764

` CUTTING DEVICE Filled Nov. 19, v1928 E. y A vw JUL Patented. .July 29, 1930 y UNITED STATES ERNEST J'. BEATTIE, OF FALL RIVER, MASSACHUSETTS, ABSIGNOR T0 CLIFTON B. LEECH, OF FALL RIVER, MASSACHUSETTS CUTTING DEVICE application mea november 19, 192s. seriai no. 320,376.'

This invention aims to provide a novel cutting device, more particularly designed for cutting plaster casts employed in surgery and the like to facilitate removal of the same.

In applying these casts, a common practice is to wrap the limb or partthat is to be enclosed with one or more layers of non-absorbent cotton sheet wadding and then apply thereto several layers of preferably wet cot- Y ton gauze or other open mesh fabric impregnated with dry plaster of Paris, the latter' also being introduced between the windings until the requisite thickness of material has been produced, whereupon the entire mass is wet with water, which causes the plaster ofi Paris to assume a thoroughly hard and inflexibleV conditionv with the windings of fabric incorporated therein, such windings acting as reinforcements to prevent destructive cracking or crumbling of the plaster of Paris.

When the plaster cast shall have been in place the requisite length lof. time, usually through periods of weeks Iand sometimes months, it becomesa considerable task to remove the same; it is so hard and rigid andl oftentimes the sensibilities of the patient are such as to make it extremely difficult to fracture it to permit convenient removal.

Various attempts have been made to provide cutting devices that could be used to saw or cut the cast in various directions to permit of itsremoval, but, s'o faras I know, such attempts have not resulted in anything practicable. Small saws have been tried, but, while they are elicient in segregating the cast into parts that could be readily removed,-

they have 'been impracticable because the substantial diameter of a saw prevents the tool being advanced in any but a substantially direct line, that is to say, it isl impossible to swing it around a short curvefsuch as is' frequently desirable. if the cast is to be conveniently removed and without suiering to the patient. l

My invention provides a tool which is convenient to ,operate and which may be turned i upon comparatively short radii, this greatly conveniencing itsfuse.

In the drawing I have shown an lllustrative embodiment of my ferring to the drawing:

Figure 1 is a side view, partial section, of an illustrative embodiment of my invention;

Fig. 2 is an enlarged vertical cross-section 55 invention, and, re-

ldetail of the cutting tool and its associated parts; and Fig. 3 is an `enlarged horizontal section taken on the; line 3-3 of Fig. 2, looking,

downward.v

In the particular embodiment of my invention selected for illustration and shown in the drawing, referring rst to Fig. 1, my improved tool comprises 4a convenient and' preferably pistol-like handle 1, from which Vm5 projects an arm 2 bifurcated at its end.

In the bifurcated end of this arm is mounted a self-contained electric motor 3 which furnishes a convenient power means for operating the cutting tool. ranged in a suitable casin provided at its two ends with projecting osses 4 and 5 in which the armature is mounted to turn, the elds of themotor bein enclosed within the casing 3 and rotect'edy the latter.

One branch o the bifurcated arm 2 is ex' tended across the end of the motor and provided with a socket in which the boss 4 `is received, and the other branch of said bifurcated arm is extended down along the side so of the motor casing and is secured as by screws 6 to said casin n The armature sha tis extendedv through and beyond the boss 5, as best shown at 7 1n Fi 2,'-and the end of the armature shaft isv 85 soc etedto receive' and hold the end of the cutting 'tool 8.

The tool may be secured to the amature shaft in an desired manner, but referably the socket 1s tapered to receive the tapered 90 end 9 of the tool and atthe inner end of the socket a threaded recess is provided to receive the threaded end 10 of the cutting tool, and, as the tool is screwed into the extreme end of the socket, the tapered portion of the tool is drawn into firm contact with the tapered walls of the socket to furnish a' rigid The motor is `ar- 70 iolds the cap permanently in position upon the end ofthe boss, but permits it to swivel or turn freely upon the boss.

The tool 8 is novel in that it is relatively lo n and of small diameter and is provided wit spiral cutting teeth or lands 14, best shown in Fig. 3, with wide and open clearances or iiutes 15 between them. These teeth or lands are so made to facilitate the cut-- ting of substances or 'materials of the nat-ure of plaster of Paris reinforced with or in which is incorporated cotton libre and the like. Such a substance requires for the best results cutting teeth of considerable depth and of rather small cross-section and with relatively large clearances between them and of a high spiral pitch to causethe tool to free itself and the scarf as quickly as possible of the chips and particles removed in the act of cutting.

To steady and support the device in use and to facilitate its introduction to and passage through the work'and to protect the person of the patient, the `swivel cap 11 is provided with a depending strut 16 which extends down along the side of the cutting tool 14, preferably parallel thereto, and serves as a support for the preferably disc-like guiding and supportin 'foot 17. This foot is shown as broad and at so that it may pass readily between the person of the patient (indicated at a in Fig. 1) and the plaster cast (indicated at b in Flg. 1) and so facilitate the cutting operation. The edge of the guiding foot 17 is preferably beveled above and below its median plane as indicated at 18, 19, the upper bevel 18 being preferably the larger and more pronounced. I

Theguide foot at its upper face is provided with an inverted pyramidal socket 20 to receive the tapered end 21 of the cutting tool, said socket serving to steady the end of,

the cutting tool, and the latter in turn serves as a pivot--point or center about which the guide foot 17 may turn'about the axis of the cutting tool -which is also the axis of the swivelcap 11, the `construction being such that the swivel cap and the guide foot joined b the strut 16 may turn freely around and a out the tool and 'about the axis of the latter to facilitate the advancement and turn- "ing of the tool in a manner that will be presently described. v

The. current for the motor 3 may be conducted thereto ina suitable manner, as by vthrough which it passesto the motor con-v trolled by a conventional switch, not shown,

but typified by the dotted line 23, operable by means of a trigger-like handle 24. The strut 16 is shown provided adjacent the cutting tool with a clearing iin 25, which stands closely adjacent the cutting tool and serves to remove fromthe latter any portions of the fabric or of the substance of the cast itself that might tend to adhere to the cutting tool and interfere with the operation thereof; The presence of this clearing surface, in juxtaposition to the circle of travel of the cutting edges of the tool, also assists the spiral teeth or lands of the cutter in lifting the particles removed from the cast vertically to and above the top 'of the cast, where they may be readily pushed aside.

In operation, the cast having served its purpose and being ready for removal, the surgeon, seizing the handle of the cutting device as he would the handle of a pistol and pressing the trigger switch 24 to'set the motor in operation, presents the cutting tool to an edge of the cast much as illustrated in Fig. 1, beingcarefu'l that the edge of the flat guide foot 17 is pushed carefully between the inner edge of the cast and the skin of the member plied. Thereafter, as the'device is ushed lirmly and steadily forward, the rapi ly rotating cutting tool 14 acts much like a common form of milling cutter and cuts its way labout or upon which the cast has been aplaterally and parallel with its axis into and through the substance of the cast, cutting 'a path or scarf in any desireddirection or directions therethrough until the cast has been separated into a plurality of portions or fragments, which may be readily separated and removed without pain to the patient. l

Because of the small diameter of the cutter in the direction in which it is advanced, the path of the cut may b e made as sinuous as desired and even relatively sharp corners may be turned without inconvenience, 'and this turnin about curves of short radii is greatly ,faci itated by the swivel mounting of the guide foot 17 and its su portin strut 16, which permits said guide oot an strut to trail after the cutter, swinging from side to side as may be necessary, like the rudder of a ship, but at the same time always maintaining the guide foot sufficiently firm in its position to assure proper operation of the cutting tool.

The swivel cap 11 is'shown provided with a clamping screw 27 having a knurled head for convenient manipulation by the lingers and which may be screwed inward upon the boss 5 to clamp the cap and its attached strut and lguide foot against swiveling movement when the latter is not desired.

My invention is not limited to the particular embodiment shown.

Claims:

1. AA portable surgeons plaster cast cut- Ating device comprising a carrier having a y foot mounted thereon; a tool holder mounted on said carrier to rotate about an axis perpendicular to said guide foot; means to rotate said tool holder; and a side cutting tool 8 mounted in and toberotated by said tool l holder. l, 3. A portable surgeons plaster cast cutting device comprising a carrier; a guide foot mounted thereon; a tool holder mounted on 'said carrier to rotate about an axis perpendicular to' said guide foot; means to ro tate said tool holder; and a side cutting tool 8 mountedvin and to be rotated by said tool holder; said tool having a supporting bearing 20 in said guide foot. c v l 4. A portable surgeons plaster cast .cutting devicecomprisingy a carrier provided.

with a handle; a guide foot mounted thereon; a tool holder mounted on Asaid carrier to rotate about an axis perpendicular to said guide foot; an electric motor also mounted 3o on said carrierV and connected with and to rotate said tool holder; a iiexible electric conductor leading to said motor; and a finger control switch for'said motor mounted adjacent said handle in position to be operated by a linger of the hand grasping said handle.

5. A portable surgeons plaster cast cutting device comprising a carrier; a guide foot swivelly mounted thereon; a tool holder mounted on said carrier to rotate about an 40 axis perpendicular tosaid guide foot; and' means to rotate said tool holder.

' 6.h A portable surgeons plaster cast cut-v ting device comprising a carrier; a guide foot mounted thereon; a tool holder mount- '45 ed on said carrier to rotate about an axis perpendicular to said guide foot; means to rotate said-tool holder; and stripping means I for the cutting` tool.

7. A portable surgeons plaster cast cutting device comprising a carrier; a guide foot mounted thereon andto swivel with relation thereto; a tool holder mounted on said carrier to rotate about an axis perpendicular to said guide foot; means to rotate said tool holder; and means to securesaid guide foot against swiveling action when desired.

8..A portable surgeons plaster cast cutting device comprising a carrier; a guide foot mounted thereon; a tool holder mounted on said carrier; a side cutting tool 8 mounted thereon and to be rotated thereby; and means 'to rotate said tool holder.

In testimony whereof, I have signed my name to this specification.

ERNEST J. BEATTIE. 

